Keys and illustrations are given that enable all stages to be identified of Aedes nigripes and A. impiger, normally the only two species of mosquito found in the high arctic. First-instar larvae and pupae of both species are described for the first time. Keys and descriptions are based on material from northern Ellesmere Island.

The light brown apple moth, Epiphyas postvittana Walker, is a highly polyphagous native pest of Australia that has recently caused widespread damage to pome, citrus, and vine crops in Victoria and Tasmania. Populations of the pest were followed in a young pesticide-free orchard for two seasons and showed a survival trend of less than 1% of the total eggs laid in each season. An evaluation of its natural enemies by numerical, serological, and forced feeding techniques showed that spiders, particularly the theridiid Achaearanea veruculata (Urquhart), were valuable predators and that they were supported by chrysopids and mirids for short periods of time. Egg, larval, and pupal parasites also contributed to mortality. Brief biological notes on some of the predators are given.

A new, endemic monotypic genus of Pyrgomorphidae, Xenephias, is described from Socotra. The single known species, X. socotranus n. sp., proves to be a member of the widely distributed tribe Sphenariini. It shows some similarities to eastern Asiatic genera, but is apparently closest to the isolated east African genus Sphenexia Karsch.

The genus Taoia and two new species, Taoia exotica from Alnus nepalensis D. Don. and Callaphis nepalensis from Juglans regia L., are described. Descriptions of Chromaphis hirsutustibis Kumar & Lavigne and of Tinocalloides montanus Basu are also given, together with keys to the so far known species of Taoia, Callaphis, and Chromaphis. Tuberdefectus eastopi Kumar & Lavigne is established as a synonym of T. montanus. The taxonomic position of these aphids is discussed.

The emergence and adult activity of Aedes (Ochlerotatus) impiger and A. (O.) nigripes during 1962–66 at Hazen Camp (81°49′ N., 71°18′ W.), Ellesmere Island, N.W.T., are described.

The greater part of seasonal emergence (assayed by emergence traps) took place from shallow ponds during a period of 7–10 days, usually in early July. Emergence of A. impiger began about 3 days earlier than that of A. nigripes, and peak emergence of the two species was separated by about 4 days; males of both species normally emerged 1 or 2 days before the females. From each pond 80% of annual emergence usually occurred within 3 or 4 days. Pond-to-pond differences were correlated closely with water temperature, but delayed emergence occurred at the end of the emergence period in temporary ponds, as the ponds became dry. Year-to-year temperature differences altered both the seasonal position and the duration of emergence in a given pond by up to 10 days.

The flight activity of adults (assayed by a Visual Attraction Trap and a Malaise Trap) was greatest shortly after the period of greatest emergence, but adults, especially females, were caught for more than a month after emergence had ended. Biting by females continued throughout this period, but swarming of males was more abbreviated, especially in A. impiger. The number of adults trapped fluctuated from day to day according to weather: flight was inhibited when maximum screen air temperatures were below about 5 °C. The interval required for ovarian maturation was about 9 days in both species, and some females completed at least three gonotrophic cycles. The successive cycles were detected in the population by analysis of sweep-net catches, the proportion of gravid females caught in the traps being affected considerably by weather. Successive gonotrophic cycles were well synchronized, like emergence, in A. nigripes; retention of eggs apparently obscured such synchrony in A. impiger.

Feeding on nectar (of the flower Dryas integrifolia) was apparently needed by both sexes to maintain activity, at least upon emergence.

Year-to-year differences in the numbers of adults emerging were correlated with the amount of flight, and hence reproductive activity, permitted by weather the previous year.

These findings are summarized graphically (Fig. 21). Critical comments are made on the usefulness of some of the sampling methods employed. Some characteristic biological features of arctic mosquitoes, leading to prompt emergence in spring and permitting subsequent reproductive activity despite the low temperatures and variable weather of the summer, are discussed.

Immature stages of the rodent bot fly, Cuterebra tenebrosa Coquillett, from central Washington are described and illustrated. Redescription of both sexes of the adult fly are also provided. Larval cuticular spines and posterior spiracular patterns are distinctive for second instars. Important characters of third instars include shape and number of points on cuticular spines and papillae arrangement. C. tenebrosa parasitizes bushy-tailed wood rats (Neotoma cinerea) and desert wood rats (N. lepida) in the western United States and western Canada.

Surveys, from 1948 to 1964, showed that parasites were of minor importance in controlling the European corn borer, Ostrinia nubilalis (Hübner), in extreme southwestern Ontario. Of the three species that became established, Lydella grisescens Robineau-Desvoidy was the most widespread and the most important. Eriborus terebrans (Gravenhorst) showed considerable buildup in parts of Essex County after discovery there in 1957, and Sympiesis viridula (Thomson) was found widely dispersed, but low in density, throughout the survey area. There is an indication that parasites might be of greater importance in areas where the second-generation borer is increasing.

In Holomelina immaculata (Reakirt) periodicity of male attraction to synthetic 2-methylheptadecane, the female-produced sex pheromone, is modified by temperature cues. In the field this response interval occurs from approximately sunset to about 4 h after sunset on a warm day and night (30° to 17 °C) and for the 2 h prior to sunset on a cool day and night (23° to 16 °C).

In laboratory studies at 24 °C female H. immaculata placed in continual scotophase have an endogenous calling rhythm, but they are apparently inhibited from calling by constant photophase. In 16:8 or 12:12 light–dark cycles at 24 °C calling occurs from the 2nd to the 6th hour of scotophase, whereas at 15 °C calling takes place from the initiation to the 5th hour of scotophase. The critical cues governing initiation of calling behaviour are lights-off or a temperature decrease cue, and a temperature decrease signal overrides the apparent inhibitory effect of continual photophase.

Female Heliothis virescens (F.) were irradiated with 7.5, 15.0, 22.5, or 30.0 krad of γ-rays and crossed with untreated males. Then the survival and fertility of the F1 insects from these crosses and the survival of the F2 descendants were studied. The F1 survival showed a dose-dependent reduction with increasing dose, but F2 survival was normal. Likewise, we found near-normal fertility in progeny from irradiated females, regardless of dose.

The egg and five nymphal instars of Zelus socius Uhler are described and illustrated. The eggs are elongate-oval, 1.39 mm high and 0.53 mm in diameter (mean values). The mean lengths of nymphs are 2.45, 3.47, 5.64, 7.56, and 10.49 mm in the five stages, respectively. The developmental period for eggs averaged 9.0 days and the nymphal development averaged 52.6 days. There is one generation a year.

From November 1968 to January 1970, Cerambycidae (Coleoptera) were collected in Northeast Thailand, principally from the Korat Plateau Region. Sixty-two species were identified: no previous Thailand records could be found for 29 of the species.

The fecundity of the pea aphid Acyrthosiphon pisum (Harris) at 15 °C gradually diminishes as we diminish the daily photoperiod, this being maximum at 16 hours of photoperiod (55 ± 10 on variety Lincoln and 74 ± 15 individuals per parent on pea variety Perfection).

At 15 °C sex determination seems to take place between 12 and 14 hours of photoperiod, the critical phase for the change of sex being 13 hours 17 minutes of photoperiod for A. pisum. Maximum male production (57 – 63%) takes place at a photoperiod between 13 hours 4 minutes and 13 hours 36 minutes. A maximum of 90.5% of oviparous females was produced at a photoperiod of 12 hours and 10 minutes.

Entomophagous carnivoroids, especially those in which the development of the individual (ontogeny) is effected by its subsistence on the body fluids and the flesh of one host individual, show an extreme diversity in form and habit whereby their embryonic and larval stages are adapted for a highly specialized mode of life.

One of the more interesting of these adaptations is exhibited by biparental species of Hymenoptera in the placement of their haploid and diploid eggs in a particular organ or tissue of the host species. This adaptation may or may not be correlated with sex differentiation in host relations, a reproductive habit characterized either by differing oviposition responses that segregate haploid (male) and diploid (female) eggs to different kinds of hosts or, lacking such responses, by differing developmental mechanisms that segregate first instar males from first instar females.

The available information regarding the occurrence of the obligatory associations between the hymenopterous egg and a specific organ or tissue of the host, their characteristics, and pertinent physiological prerequisites are summarized.

Basically, these associations appear to be dependent on (1) the gravid carnivoroid usually being free of any physiological pressure (or urge) to oviposit despite the presence of eggs ready for deposition in the ovary and/or stored in the oviduct and (2) the limitation of egg deposition to the moment when the tip of the female’s ovipositor makes contact with a host or the spoor of the host. Freedom from oviposition pressure derives from the female’s ability to dispose of her "ripe" ovarian eggs by methods other than deposition, that is, either by storage in enlarged oviducts or by resorption into the bloodstream.

The control of larvae of the cabbage looper, Trichoplusia ni, and the imported cabbageworm, Pieris rapae, by viruses, bacteria, and chemical insecticides was compared. In small field plots five applications of the nuclear-polyhedrosis virus of T. ni (1.8 × 1011 polyhedra/acre) and the granulosis virus of P. rapae (4 ×1011 granules/acre) controlled the respective host larvae as well as five applications of the chemical insecticide methomyl (0.5 to 1 lb/acre). Dipel HD-1 (0.25 lb/acre) and Thuricide HPC (60 fl. oz/acre), formulations of Bacillus thuringiensis, were as effective against T. ni larvae as methomyl but not as effective as Fundal (0.5 lb/acre) or Dipel at a higher rate (0.5 lb/acre). The control obtained by combinations of viruses with endosulfan or methomyl suggested an effective method of reducing use of chemical insecticides. Control of T. ni and P. rapae in plots up to 3 acres in area in growers’ fields demonstrated the effectiveness of the viruses when used as commercial insecticides.

Aphalara monticola sp. n. is described from 37 ♂ and 49 ♀ collected from Rumex pauciflorus Nutt. in the Kananaskis Valley, Alberta, Canada. A. monticola is closely related to the Nearctic A. rumicis Mally and the Palaearctic A. exilis (Weber & Mohr).

A new genus, Knightomiris, is proposed for Lygus distinctus Knight. Diagnostic features of the genus, male genitalia and the adult of distinctus are figured, and additional records on distribution are given.

One hundred years ago the theory of evolution was new in men's minds and battles still raged between the protagonists and the antagonists. But this was not the first time that biologists had been divided. Much earlier they argued about the moral and ethical use of microscopes to aid their work. Many felt that microscopes were totally unnecessary and that there was more than enough to see with a good pair of eyes and the occasional use of the hand lens without resorting to such contraptions. Some went a stage further and insisted that God would have given us better eyes if he intended us to study the minute.

Immature stages of the pea aphid, Acyrthosiphon pisum (Harris), from viviparous, parthenogenetic populations, were exposed to hot and cold temperatures outside the favorable zone. Between 34.5 °C and 41.0 °C, time to 50% mortality (LT50) decreased approximately according to the relation log Y = 10.30−0.22X. From −9 °C to −12 °C, LT50 decreased rapidly and changed little with further temperature decrease to −16 °C.

Survival was affected by acclimation which was complete after 1 to 2 days. Acclimation to temperatures between 10 °C and 25 °C changed LT50 by as much as 1.3 times at 39 °C and 2 times at −12 °C.

Temperature tolerance increased with age.

In four studies with loblolly pine bolts over a 2-year period, absence of the normal complement of mycangial and ectodermal fungi, or absence of mycangial fungi alone, caused a significant decrease in number of progeny, progeny/gallery, progeny/cm of gallery, and ratio of increase of Dendroctonus frontalis Zimmerman. Initial emergence of progeny was delayed 13 to 24 days. Absence of fungi had no effect on number of successful attacks, length of ovipositional gallery, and number of egg niches/cm of gallery.